Wonder why it doesn't translate to real world performance.
btw, I expect more too from this 253nm. why so slow nia. If city b segment sedan can touch 8 second, I think it will sell like hot cakes
Gearbox or transmission do 2 things 1)change speed 2)convert torque.
- output gear bigger than input gear = reduce speed, and increase torque
- output gear smaller than input gear = increase speed, and reduce torque
both speed and torque change at the same proportion, one up, the other one down at same ratio.
Which means the horsepower remain constant regardless what gear you are in, only reduced by friction loss. Torque is work, horsepower is work done per unit time. You can take it as how frequent it can apply the torque. Eg:. engine1 100nm 100hp, engine2 50nm 100hp. Let's simplified with the max torque happens at max rpm. Engine2 need double the rpm to reach same 100hp.
For both to move at same speed
- engine1 1000rpm 100nm with 1:1 ratio output 1000rpm 100nm 100hp.
- engine2 2000rpm 50nm with 2:1 ratio output 1000rpm 100nm 100hp.
Electric motor spins very fast, 10,000rpm is very common. I don't have i-MMD traction motor detail spec, for your reference Volvo ERAD motor top up at [email protected]/h, Model 3 Long Range motor [email protected]/h. Thus electric motor has speed reduction gear, which is good. Eg:. 10:1 drop where motor spin 10 rotation, wheel spin 1 rotation, and torque is 10x on the wheel.
Everything are nice and positive for the RS until this point. Here's the 2 limitations.
- First, everyone knows electric motor torque drop off at higher rpm. But Honda never publish the data, we don't know how's the performance, don't know rpm when it hit 108hp, don't know 253nm rpm range. Generally the max torque will only sustain 1/3 to 1/2 of the max rpm range. So expect the 253nm last until 50km/h - 60km/h, a wild guess, depends on the speed reduction ratio and motor torque curve.
This is still ok, consider in ICE when we shift to higher gear, the torque on the wheel drop as well. ICE can get 16:1 - 20:1 (first gear times final drive ratio), more aggressive than electric motor. 2nd gear down to 9:1 to 12:1, and 3rd gear 6:1 to 8:1. So, with more aggressive 1st gear, a 160nm-170nm car might get similar or higher torque on wheel at the first gear.
- The biggest limitation is the 1.5L is only 97hp and the battery is also small 1.3kWh. Conservation of energy, the electric motor can only consume as much power as the engine able to charge the battery. In this car, the engine is less powerful than the electric motor, and charging rate also limited by the generator power. If you in constant high load all the time, you can't get more than 97hp, although this is unlikely to happen on real world. Honda quoted 60% pure EV at 40km/h, and 30% pure EV at 60km/h. The bigger sibling like CR-V, Accord hybrid get 50% pure EV at 60km/h, 30% pure EV at 100km/h. The number are all for stable cruising. So you can see, the ICE won't be able to keep up the charging if you drive aggressively.
It is a utility car for urban usage, designed for low speed city traffic jam economy. Want a fast car, go buy a proper fast car.